Suresh Vegesna is bracing for the worst as he leaves Santa Clara and heads to Tuolumne County for the long weekend.

His vacation home outside Yosemite National Park is close to the huge wildfire torching forests and scarring mountainsides. The area - at least much of it - promises to be anything but the scenic wonderland that Vegesna signed up for when he bought his family's getaway with its deck and big Sierra vistas.

"I'm kind of mentally prepared," he said. "It's not going to be a pretty sight."

Bay Area residents like Vegesna are thankful that the Rim Fire, which has grown into the largest wildfire in Sierra history, has not caused major injuries or widespread property damage - outside of the destruction of the city of Berkeley's Tuolumne Camp.

Still, owners of vacation retreats are saddened by what's happened to their mountain paradise. Some who bought rustic abodes because they were nestled in the pines worry they might have to settle for a moonscape for a while.

"After seeing green trees and now having to see the charred remains from the fire, it's going to be disappointing," Vegesna said.

The full extent of the Rim Fire's damage is yet to be known. The blaze, which began Aug. 17 in a remote section of the Stanislaus National Forest near Groveland, has scorched more than 311 square miles of land, 11 homes and three commercial structures and is 32 percent contained, authorities said Thursday.

The cost of the firefight has grown to $39 million, said Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection. Almost 5,000 firefighters are involved. The cause of the blaze is not known.

On Thursday, more ground crews, extra planes and even a drone capturing aerial images helped firefighters slow the advance of flames. While more than 4,500 homes remained threatened - many on the fire's northwest edge - officials expressed optimism that the blaze will be fully contained within three to four weeks.

Much of the conflagration has been confined to remote backcountry. But inside and outside Yosemite, its toll on the landscape will be evident.

"What we don't know yet is: Is it going to look like the surface of the moon and the day after Armageddon, or will the trees live and you'll just see some scarring on the bark?" said Larry Hebb of Half Moon Bay.

Hebb bought vacation property in Pine Mountain Lake outside Groveland 12 years ago to relive the summers he spent on a lake in the Midwest before moving to the Bay Area. He's hiked and floated in many places that have recently hit, including the south fork of the Tuolumne River and the Hetch Hetchy Reservoir in Yosemite.

Kimberly Darr, owner of Century 21 Wildwood Property in Twain Harte, expects most homeowners near the fire won't be disappointed when they return to their property. Even if there are blackened trees in one direction, she said, there will be views of pristine forest in another.

"Most of what's burned is in steep rugged canyons. That's not areas where people have homes," she said.

Darr anticipates that sales of vacation homes might dip slightly in coming months because of the blaze. But she thinks the trend won't last once people realize there's still beautiful scenery to be had.

Oakland resident Lee Zimmerman, who owns the historic Evergreen Lodge near Yosemite's Highway 120 entrance, got a glimpse of the damage this week when he returned to his property under the escort of firefighters. He said things are not as bad as he expected.

"Looking at the maps, it looks like the whole area has burned. But the fire passed through various points and didn't burn everything," he said.

The ground is charred, but green forest still stands not far away, he said. While flames licked at his 92-year-old lodge and neighboring Camp Mather, run by the city of San Francisco, the landmarks remain.

"They didn't burn, thanks to the heroics of the firefighters," Zimmerman said.

Pacifica resident Carolyn Miller, who owns a vacation home much farther north off Highway 108, said that even if the fire blackened hillsides in her area, it marked a natural event that she can appreciate.